The chewing of khat is central to many segments of society in the Republic of Yemen. Three quarters of Yemeni adults chew khat leaves each afternoon, for a period lasting at least five hours, while preparation for a chew often occupies a large chunk of time in the morning. Yemeni citizens spend a quarter to a third of their income on khat; it has become so central to Yemeni life that some of the poor will forego food in favor of it. There is great social pressure to participate in khat chews, despite the expense - those who decline are labelled outcasts.

"Qat... is the opium of our people. It is the green Imam who rules over our republic. It is the key for everything and it is central to all our social occasions. It is the unexplainable that explains everything." - Abdul-Karim Al-Razihi

Both men and women chew khat, although separately. Khat chews typically begin after lunch (which is the main meal of the day), with each chewer bringing his orher own khat. Chews are usually held in private homes, but merchants and laborers will chew at their stalls or job sites (although government workers are now forbidden to chew during work hours). The event lasts throughout the afternoon, and is an occasion for social interaction and camaraderie between the attendees. Tea with milk is often served at the end of a khat session, after which the participants disperse and return to their homes or places of business.

Khat is typically grown on mountain terraces at an elevation of at least 1000m; it is only good for 24-48 hours, so an extremely efficient transportation system has developed to ensure that it reaches markets before losing potency. Yemeni men tend to the trees, stay up at night to guard them, and harvest the leaves, while women handle livestock. Khat currently occupies 3.5% of the total cultivated area in Yemen, although that percentage is increasing. It is a relatively benign crop, although it encourages erosion and tends to deplete soil of nutrients. It grows much better when irrigated, which has led to increased development of irrigation and other water technologies in regions where the trees are cultivated.

The quality, both real and perceived, of khat varies widely, with the finest varieties costing up to $40 or $50 a day. The ability to judge the quality of khat, or to get a good bargain with its merchants, are held in high regard - khat snobs are the Yemeni equivalent of the beer or wine snob. Quality is judged by the region, district, and even field in which the khat was grown; the position of the leaf on the tree is equally relevant. A general rule of thumb is that khat that comes from longer branches is better. Pickings from the lower branches are scorned by image-conscious chewers.